Lock top container



Patented Dec. 31, 1946 Loox 'rop coN'rAmEa Frank J. OBrien, Pelham Manor, N. Y., assigner to Continental Can Company, Inc., New York, N. Y., a corporation of New York Application December 28, 1944, Serial No. 570,185 I 2 Claims.

The present invention relates to improvements in metal containers, and more particularly to a metal container having a lock top closure therefor.

An impor-tant object of the invention, is to provide the upper end of the container with a smooth even surface to facilitate sealing when the closure is positionedV thereon.

Another object of the inventionv is to provide the upper end' of a container with a double seamed collar or ring for the purpose of producing a relatively wide smooth and even sealing surface for a compound lined cover or top.

A further object of the invention is yto provide a container of the above type wherein the collar or ring ts within the upper end of the container and is double seamed thereon to form .a rigid, smooth surface around the top edge of the container to facilitate sealing when the closure is applied thereto.

The above and other objects of the invention will in part be obvious and will in part be hereinafter more fully pointed out.

In the drawing:

Figure 1 is a side elevational View, partly in section, of a container embodying the features of the present invention.

Figure 2 is an enlarged fragmentary detail sectional view illustrating the position of the ring relative to the container prior to the double seaming operation.

Figure 3 is a similar view after .the double seaming operation has been performed.

Figure 4 is an enlarged fragmentary detail sectional view with the cover locked on thecontainer.

In the manufacture of containers,f it is essential that closure means be provided which will tightly seal the open end of the container. In vmetal containers, such as cans,it is conventional to employ a side seam extending longitudinally through the length of the can and including a lapped portion at least at the upper end portion of the seam, and when the upper edge of the can is rolled to form a seat for a closure, this double thickness lap seam creates an open space or uneven surface through which leakage is liable to occur. In order to obviate this possibility, the present container is provided with a seamless ring which isv rolled on the top edge of the container to form a smooth even surface for a cornpound lined cover.

Referring .to the drawing for a more detailed description thereof, the improved container is generally designated by the reference numeral 5 and comprises a body portion 6 to which a bottom end I is secured in the usual manner. The body portion 6 is preferably cylindrical and its upper end 8 is left open and is adapted to be closed by means of the lock top or cover generally designated by .the reference character A.

The upper end 8 of the body portion is offset inwardly to form a shoulder 9 and an annular rim IIJ. The rim I0, during the fabrication of the container, is formed with a flange I I extending at right angles thereto, adapted to be .bent downwardly during the' seaming operation. A drawn metal ring l2. is positioned within the upper end of the -body portion 6 being confined by the annular rim I0 thereof, which ring is formed with a flange I3 extending at right anglesl to the container and substantially parallel with the flange Il, as shown in lFigure 2. After positioning the ring within the container a spinning operation is performed in order to cause the lower end I4' to follow the shape and contour of the shoulder 9 and at the same time be brought into tight bearing engagement with the.entire upper end of the body pcrtion.-

The container 6 with the ring I2 firmly `held therein is then subjected to a double seaming operation to provide the construction shown in Figure 3. By this double seaming operation .the flangeJI is bent downwardly to a position substantially parallel with the rim III and the ange I3 is bent downwardly and upwardly so that the end I 4 thereof is positioned between the down- .turned flange II and rim II) as clearly shown in Figure 3. This double seaming of the ring I2 on the upper end of the container provides a more rigid construction and at the same time produces a relatively Wide, smooth and even surface I5 for the closure A to be sealed thereon. In other lwords, there are no stepped or uneven surfaces which would tend to produce a faulty seal when a lock top closure is applied to the upper edge of the container.' i

The type of closure used with the new and improved container is well known in the art and genera1ly comprises a body IISv that is depressed centrally to form a central body portion I'I and a heel I8 which fits within the ring I2 and cooperates with the skirt portion I9 in forming an annular channel 20. The skirt I9 is dimensioned .to tclosely about the body wall of the container, and the end thereof is bent outwardly and'inwardly at right angles to form an annular stiifener hem 2I. The annular channel 20 carries a sealing compound B for sealing the contents of the container when the cover is locked thereon. The cover is locked on the container through the medium of the spaced thread portions 22 formed on the body just below the offset 9 and which are engaged by complementary .thread portions 23 formed on the cover. A slight rotation of the covex` will cause the thread portions 23 to engage the thread portions 22 forlocking the cover in position on the upper end of the container, With the cover in locked position, the sealing compound I9 will follow the contour of the surface I5, which surface is smooth and rigid, for effectively sealing the contents of the container. The upper end of the-container is reinforced by reason of the double seamed ring thus withstand- -ingeconsiderable pressure in the application of the closure` without any appreciable distortion. The surface I5 is suiliciently wide and smooth to accommodate the sealing compound held within the'channel 20 so that the contents of the container will be eectively sealed. M

While a preferred embodiment of the invention has been shown and described, it is to be understood that the, invention is not limited to the illustrated embodiment -but may be variously modified without departing from the spirit and 4 metal ring forming 4at the upper end of the seam a continuous unbroken rounded sealing surface, a closure for -said container, said closure having a central depression surrounded by a cylindrical y wall and a depending skirt spaced outwardly from said cylindrical wall and joined thereto by a curved portion conforming to the curvature ofi.

2. A metal container comprising a body having 5 an open upper end, said open end portion being oiset inwardly forming in said body a shoulder, a drawn metal ring fitting within the open end 'of the body and closely contacting said shoulder,

.said Imetal ring being extended outwardly overr the -body wall and rolled into a double seam with the body wall, said drawn metal ring forming at the upper end of the seam a continuous unbroken rounded sealing surface, a closure for said container, said closure having a central depression surrounded by a cylindrical wall and a depending skirt spaced outwardly from said cylindrical wall and joined thereto by acurved portion conform; 

